Sealant system for waterproofing welted footwear

A method for waterproofing a stitched footwear construction, which construction meets a standard water immersion flex test, where a first footwear component is secured to a second footwear component by stitching with a threaded needle, the needle being dimensionally larger than the thread it carries, which method comprises:

• applying a sealant to the surface of one of said components, the sealant comprising an amorphous polyolefin comprising greater than 99% propylene ethylene copolymer, the amorphous polyolefin present in the composition in an amount of 20 to 90% by weight based on the total weight of the composition, and an amorphous polyalphaolefin copolymer, the amorphous polyalphaolefin present in the composition in an amount of 80 to 10% by weight based on the total weight of the composition, the sealant characterized by a viscous core;
• combining the components to form a first component/sealant/second component laminate;
• and
• stitching the components together with the threaded needle, the needle forming a hole through the laminate, the needle carrying the viscous core of the sealant into the hole and filling and sealing the hole, the sealant thereby forming the stitched construction, the stitched construction having a water-impermeable seal between the stitched components and characterized in that the stitched construction exceeds the water immersion flex test at more than 8,000 flexes.